Technical Abstract:
Salmonella enteritidis (SE) is an important pathogen for the layer industry, primarily because of its ability to infect hens and ultimately contaminate egg contents. Studies have shown that stress situations such as flock recycling (induced molting) can increase SE problems in the flock. Studies were conducted which examined the use of antibiotics and competitive exclusion (CE) in reducing SE problems during a molt. The treatment comprised of oral administration of enrofloxacin (Baytril; 10 mg/kg/day in drinking water) for 10 days followed by 2 doses of oral CE (Aviguard) treatment at 48 and 96 hours. The birds were examined for SE shedding 4 and 10 days following the completion of therapy. The SE shed rate was 33% and 25% in untreated birds 4% and 0% in the Baytril/Aviguard birds on the two test days. These results indicate that treatment of SE- positive laying hens postmolt with Baytril and CE cultures can substantially reduce SE problems due to molting and would be a good alternative to diverting eggs for pasteurization or slaughtering the infected flock.